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Research on the transformation of Oil Palm Empty Fruit Bunches (OPEFB) through pretreatment process using ionic liquid triethylammonium hydrogen sulphate (IL [TEA][HSO4]) was completed. The stages of the transformation process carried out were the synthesis of IL with the one-spot method, optimization of IL composition and pretreatment temperature, and IL recovery. The success of the IL synthesis stage was analyzed by FTIR, H-NMR and TGA. Based on the results obtained, it showed that IL [TEA][HSO4] was successfully synthesized. This was indicated by the presence of IR absorption at 1/λ = 2814.97 cm−1, 1401.07 cm−1, 1233.30 cm−1 and 847.92 cm−1 which were functional groups for NH, CH3, CN and SO2, respectively. These results were supported by H-NMR data at δ (ppm) = 1.217–1.236 (N–CH2–CH3), 3.005–3.023 (–H), 3.427–3.445 (N–H+) and 3.867 (N+H3). The TGA results showed that the melting point and decomposition temperature of the IL were 49 °C and 274.3 °C, respectively. Based on pretreatment optimization, it showed that the best IL composition for cellulose production was 85 wt%. Meanwhile, temperature optimization showed that the best temperature was 120 °C. In these two optimum conditions, the cellulose content was obtained at 45.84 wt%. Testing of IL [TEA][HSO4] recovery performance for reuse has shown promising results. During the pretreatment process, IL [TEA][HSO4] recovery effectively increased the cellulose content of OPEFB to 29.13 wt% and decreased the lignin content to 32.57%. The success of the recovery process is indicated by the increasing density properties of IL [TEA][HSO4]. This increase occurs when using a temperature of 80–100 °C. The overall conditions obtained from this work suggest that IL [TEA][HSO4] was effective during the transformation process of OPEFB into cellulose. This shows the potential of IL [TEA][HSO4] in the future in the renewable energy sector.

Importantly to study the coastal vegetation from Kekara Laut (Canavalia maritima Thou.) to observe the antibacterial agents towards Staphylococcus epidermidis. The purpose of this study to examine the variation concentration effect of an ethanol leaf extract from Canavalia maritima Thou. in inhibiting the growth of S. epiderimidis bacteria. The leaf of Canavalia maritima Thou. was prepared using a physicochemical method to obtain ethanol extract, then varied in several concentrations, namely 5% w/v; 10% w/v; 15% w/v; and 20% w/v. Based on these results, we obtain the ethanol leaf extract can inhibit the growth of S. epidermidis with a concentration of 15% w/v for 24 hours having an inhibition zone of 17.17 mm. The statistical analysis test was very significantly different from all antibacterial tests, the value of F count was 682.1 with F table (3.48), at the level of α = 0.05 (3.48) and α = 0.01 (5.99), which indicates that H0 is rejected, but using the Variance method in the Newman-Keuls range approach shows that each concentration has a good inhibitory ability. The use of Canavalia maritima Thou. leaf extract in low concentrations can significantly inhibit bacterial growth (bacteriostatic).

Electrochemical studies in detecting persistent organic pollutants (POPs) have attracted a lot of interest from researchers, especially the carbon paste electrode (CPE). The research objectives were to determine the electrochemical characteristics of TiO2/Ag-Li on the CPE in the system Fe2+/Fe3+ and determine the fipronil in solution. TiO2/Ag-Li preparation was carried out by using the sol-gel method. Electrochemical performance of CPE was applied by cyclic voltammetry. The system developed was a reversible redox reaction and have peaks Ipa 110 µA and Ipc 105 µA. We also found that the composition of the best modifier addition to CPE was using TiO2/Ag-Li with a mass of 0.005 g. The optimum scan rate for the measurement of the fipronil test solution was obtained at 0.2 V/s with an Ipa value of 15 µA and an Epa value of 0.40 V. Based on the plot between the root scan rate and the oxidation current of the solution containing fipronil, the obtained R2 value was 0.9806. This research provides the development of modifier CPE material with the well electrochemically performance and considered as a very effective monitored system for the environment contaminated by POPs waste.